#include <stdio.h>
#include <ctype.h>
#include <string.h>
void trim_whitespace(char *s) {
while (isspace((unsigned char)*s)) {
strcpy(s , s + 1);
}
if (*s == 0)
return;
char *end_s = s + strlen(s) - 1;
while (end_s > s && isspace((unsigned char)*end_s)) end_s--;
end_s[1] = '\0';
}
int main() {
char s[50] = " c python c++ java php ";
trim_whitespace(s);
puts(s);
}
/*
run:
c python c++ java php
*/